Cush drive unit

[Boostinjdm]

Your right about the bolts in shear.  My original Idea was to start with a 1" or so thick center and turn it down to leave a flange to bolt the sprocket to.  Eight bolts?  I only see four.  how does the center attach to the shaft?

[Engineer]

I wouldn't want to put the sprockets on the side plates, because then screws would be in shear. Right now the PU slugs react on the sprocket itself. The screws see some shear but not nearly what they would if the side plates were sprockets. For assembly all I had to do was chase and tap the holes and add the c'sinks. The flat hd. screws act like dowels to keep the side plates located. Next I have to clean up the center bore and open up side plate holes for the bearings. This will be done on the lathe with the sprocket assembled like you see it. The 5 pieces will then be stamped so they always go together as they were machined.
I'm also turning the od of the bronze bearings and leaving a 1/16" thick flange for thrust.
no splines or welding it's all torqued down with the eight bolts. (The spider has 8 holes on a 2-1/2" bolt circle.)

I see, so there is no shaft.....  Just the CV cups capture the carrier bearings and bolt to the spider to clamp it all together.  Very nice!

[Boostinjdm]

tube spacers?  ok I'm lost now.  I guess I better go back to busting lathe and plaster and wait for your pics so I understand better.

Total time logged in: 4 days, 14 hours and 1 minutes.
If my girlfriend knew about this she'd kill me. I could have gotten a lot done on the house in that time.

[Boostinjdm]

I see, so there is no shaft.....  Just the CV cups capture the carrier bearings and bolt to the spider to clamp it all together.  Very nice!

makes sense now. so the down side is big ole expensive bearings?

[Rick S.]

Yes, but the cv cups only go halfway into the bearings. Then there is a second spacer that goes from bearing to the spider. (same for both sides) The second spacer is what the bronze is riding on.
Basically what you said though.

[Boostinjdm]

oo ooo, Idea!  bolt cvs directly to the center spider and buy bigger more expensive bearings to mount directly to the cvs.  Effective flange width, 1".  Upside, ultra narrow and less pieces.  Down side, high dollar bearings and you'd have to cut a slight shoulder on the cvs to capture the bearings.

I reserve the right to a cut of any money made off that Idea...or at least some prototype pieces. 

[Engineer]

Cool, so what is the bearing OD?  And do they make flanges for them or will you have to make a custom housing?

[Boostinjdm]

how bout just making the side plates out of bronze instead of pressing in separate pieces?

[Boostinjdm]

Ok, my idea needs refinement.  I'd better go do something else while I think about it.... I'm still watching though.  Keep the post coming.  this is very interesting to me.

[fabr]

Two chains could easily be done by making the covers the sprockets.
Not a bad idea either, but it would add a little width. Right now the type 4 cv flanges are 4-1/2" apart. 930's would be 5"
I did look at standard spiders, but the way I have it designed, it was easier and cheaper to do it this way. For $17 I can buy 24" of poly rod. enough for 3 units. Plus I can play around with different durometers without spending too much cash. 

The curved jaw spiders are cheap and available in 4 different shore.

[fabr]

The spider is one piece 1" thick waterjet with a 2" id.  Everything sandwiches together with eight 5/16-18 x 3"  soc. hd. cap scrs. The slugs are a slip fit in the housing. Yes they could be cast. We have used the 2 part PU before at work.

IMO you won't want to use 2 part PU poured in place. The WJ spider tho would be good.

[Yoshi]

If your wanting to put a dual sprocket setup on it and not stress the bolts more, instead of having 3 center pieces, have 1 thick one, machined with 2 sets of sprocket teeth and a groove down the middle.

[Rick S.]

Hey, these are all great ideas, but I've already got this thought out.
I don't want or need two chains and the spiders I've seen just won't fit the design.
The waterjet spider I'm talking about is steel. Maybe I shouldn't be calling it a spider, it has four legs. This spider (gear) is driving the PU slugs.
It's pretty simple really. I just slice off eight PU slugs and drop them into the housing.
The large bearings are 75mm id x 115mm od and not expensive. Under $60 for the pair.
The cv flanges are custom and machined to fit the bearing id.
The same bearings and set up used in Artie's casting alum. thread.
This pic. should explain it.

[Yoshi]

Pretty similar to this...

[Rick S.]

Yes, but it looks like that doesn't use bearings.
It looks like the driver rides on the inside of the hub.
Seems like it would wear out, but I could be wrong. Who makes it?